Human-powered helicopter

Updated: Feb 28, 2013 20:02 IST

In order to win the $250,000 American Helicopter Society Sikorsky Prize, a helicopter must fly under human power for at least 60 seconds and momentarily reach an altitude of 3 meters while remaining within a 10 meter square box. (AP)
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In order to win the $250,000 American Helicopter Society Sikorsky Prize, a helicopter must fly under human power for at least 60 seconds and momentarily reach an altitude of 3 meters while remaining within a 10 meter square box. (AP)

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